How does the tufted and rumpless gene work?

[Trish1974]

If an araucana rooster that had tufts and was rumpless bred non araucana hens (like orps and australorps), would the tufts or rumplessness carry over to the offspring? Would it be a 50/50 split?

How about the same rooster over an ameraucana hen? Would the tufts or muffs be dominant?

 

[The Moonshiner]

Tufts and rumpless are both dominate.
Rumpless...two copies bred to two copies equals all rumpless two copies.
Two copies bred to no copies equals all rumpless one copy.
One copy bred to one copy equals 25% no copies, 50% rumpless one copy, 25% rumpless with two copies.
There are modifying genes also in play. Any rumpless with only one copy usually aren't 100% rumpless. Most have a feather or two or three.
Tufts are not related to beards and muffs. They can have all three.
Tufts is dominate but lethal. One gene equals tufts. Two genes equal chick dying in shell.
One copy bred to no copy equals 50% tuft and 50% no tufts.
One copy bred to one copy equals 25% no tufts, 50% tuft and 25% die in shell.
All tuft are not created equally. Some have poor tufts other beautiful large tufts and some are only tufted on one side.

 

[Trish1974]

Got it! Thanks!